High Content Sodium Ibuprofen Granules, Their Preparation And Their Use In Preparing Non-Effervescent Solid Dosage Forms

ABSTRACT

Granules of racemic sodium ibuprofen dihydrate formed from components specified herein have very desirable properties and can be effectively used in conventional rotary press tableting equipment without operational difficulties often encountered in actual practice. Their preparation by a wet granulation process, the wet granule compositions, formulations adapted for preparation of solid dosage forms utilizing a rotary press, solid dosage forms, and methods of preparing solid dosage forms in a rotary press are also described.

TECHNICAL FIELD

This invention relates to high content granules of ibuprofen medicaments made from ibuprofen sodium salt dihydrate, to process technology for producing such granules, and to uses of such granules in preparing non-effervescent solid dosage forms for oral administration.

BACKGROUND

According to the published literature, solid dosage forms made from sodium ibuprofen are superior in pharmaceutical kinetics (i.e., they enter and peak in the blood stream more rapidly than other solid dosage forms of ibuprofen). However, despite intensive research in the field, it remains difficult to form solid dosage forms from sodium ibuprofen using conventional approaches. One of the difficulties is that sodium ibuprofen dihydrate has poor flowability characteristics and thus tends to cake readily even when blended with conventional anti-caking agents such as colloidal silica or talc. The poor flow characteristics of sodium ibuprofen dihydrate, even though formulated with flow improvers, can result in erratic weight variations in the solid dosage forms such as tablets and caplets being produced. Another difficulty in forming sodium ibuprofen tablets and caplets is the tendency of sodium ibuprofen dihydrate to form film coatings on the punch surfaces of the rotary press. Such film coatings, when not excessive, are nonetheless undesirable because they reduce the shininess or gloss of the tablets or caplets being formed. If excessive coatings are formed on the punch surfaces, several operational difficulties are encountered. First of all, defects in the tablets or caplets being formed will occur. Secondly, erratic punch operation results. And thirdly, unacceptable variations in tablet or caplet weights can also be experienced. Any of these operational difficulties in turn will result in the need to shut down the equipment in order to clean the punch surfaces.

It would therefore be of considerable advantage if a way could be found of forming sodium ibuprofen compositions capable of being more readily converted into solid dosage form such as tablets or caplets using conventional rotary press tableting equipment without encountering the various difficulties referred to above. It would also be of considerable advantage if a way could be found of producing highly flowable granules from sodium ibuprofen dihydrate so that the dosage level of hard shell capsules filled with the granules can be kept more uniform.

This invention addresses all of the foregoing needs in an effective manner.

BRIEF NON-LIMITING SUMMARY OF THE INVENTION

Pursuant to this invention, it has been found that granules formed from racemic sodium ibuprofen dihydrate (a.k.a. sodium 2-(4-isobutylphenyl)propionate dihydrate, and hereinafter referred to more simply as sodium ibuprofen dihydrate), sodium carbonate, and polyvinylpyrrolidone (a.k.a. 2-pyrrolidone, 1-ethenyl-, homopolymer) by a wet granulation process has very desirable properties and the granules, when properly formulated, can be effectively utilized in conventional rotary press tableting equipment without encountering the various difficulties referred to above. Moreover, it has been found that in the granulation operation and in the rotary press tableting operation, the advantageous results made possible by this invention can be achieved even though the amount of the sodium carbonate in the granules is only 3 wt % or less. Indeed, it has been found possible to produce excellent tablets from granules of this invention in which the granules contained only 2 wt % of sodium carbonate.

The fact that such extremely small amounts of sodium carbonate are effective in the formation of the granules and resultant tablets formed therefrom is also advantageous in connection with tablets consumed by more elderly persons. As is well known, as an individual ages, the acidity in the digestive tract tends to decrease, and thus such low levels of sodium carbonate in the tablets of this invention do not overly upset the digestive process in such individuals.

In one of its process embodiments, this invention provides:

A) A process of preparing a highly dispersible free-flowing granules of sodium ibuprofen dihydrate, which method comprises:

-   -   bringing together in a high shear granulator components         comprised of (i) at least 80 parts by weight on a dry basis of         sodium ibuprofen dihydrate, (ii) 1 to 4 parts by weight on a dry         basis of sodium carbonate, (iii) 1 to 15 parts by weight on a         dry basis of non-crosslinked polyvinylpyrrolidone, and (iv) 8 to         12 parts by weight of water based on the total weight of (i),         (ii), (iii), and (iv) to form a wet mixture;     -   granulating said wet mixture in said high shear granulator to         form wet granules;     -   drying wet granules to form dried granules having a moisture         content in the range of about 11 to 15 wt %, and preferably in         the range of about 12 to about 15 wt %, as determinable by         measurement of weight loss at 110° C.; and     -   removing by sieving dried granules having a particle size         greater than 16 mesh.

Among the preferred process embodiments of this invention is the following:

B) A process as in A) above wherein the granulation of said wet mixture in said high shear granulator is conducted for a period of time such that after drying said wet mixture, the dried granules exhibit during differential scanning calorimetry a phase transition peaking in the range of about 100° C. to about 102° C., and wherein the size of the DSC peak, which peak corresponds to solids-to-solids phase transition, is at least about 150 joules per gram.

Among its composition embodiments, this invention provides:

C) A highly dispersible, free-flowing granule composition having a high content of sodium ibuprofen dihydrate, which composition is formed from components in powder form, said components comprising (i) 80 to 98 parts by weight of sodium ibuprofen dihydrate on a dry basis, (ii) 1 to 4 parts by weight of anhydrous sodium carbonate on a dry basis, and (iii) 1 to 15 parts by weight of non-crosslinked polyvinylpyrrolidone on a dry basis. D) A sodium ibuprofen dihydrate formulation adapted for preparation of solid dosage forms using a rotary press, which formulation is formed from components which comprise:

-   -   about 40 to about 100 wt % of a granule composition as in C)         above;     -   0 to about 25 wt % of microcrystalline cellulose, calcium         hydrogen phosphate, or both;     -   0 to about 8 wt % of crospovidone or sodium croscarmellose;     -   0 to about 0.5 wt % of colloidal silica;     -   0 to about 10 wt % starch; and     -   0 to about 2 wt % stearic acid, magnesium stearate, or both.

Among preferred composition embodiments of this invention is the following:

E) A formulation as in D) above wherein said formulation exhibits during differential scanning calorimetry a phase transition peaking in the range of about 100° C. to about 102° C., and wherein the size of the DSC peak, which peak corresponds to solids-to-solids phase transition, is at least about 150 joules per gram.

Other embodiments, features, and advantages of this invention will become still further apparent from the ensuing description, accompanying drawings, and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a differential scanning calorimetry curve of the granules of this invention produced in Example 11.

FIG. 2 is a differential scanning calorimetry curve of the granules of this invention produced in Example 12.

FIG. 3 is a differential scanning calorimetry curve of the granules of this invention produced in Example 13.

FIG. 4 is a differential scanning calorimetry curve of the granules of this invention produced in Example 14.

FIG. 5 is a differential scanning calorimetry curve of granules of this invention produced in Example 15 sampled with a drier inlet temperature set at 70° C., and when the drying temperature of the granules reached 35° C.

FIG. 6 is a differential scanning calorimetry curve of granules of this invention produced in Example 15 sampled with a drier inlet temperature set at 70° C., and when the drying temperature of the granules reached 40° C.

FIG. 7 is a differential scanning calorimetry curve of granules of this invention produced in Example 15 sampled with a drier inlet temperature set at 70° C., and when the drying temperature of the granules reached 45° C.

FIG. 8 is a differential scanning calorimetry curve of granules of this invention produced in Example 15 sampled with a drier inlet temperature set at 70° C., and when the drying temperature of the granules reached 48° C.

FIG. 9 is a differential scanning calorimetry curve of granules of this invention produced in Example 16 sampled with a drier inlet temperature set at 70° C., and when the drying temperature of the granules reached 40° C.

FIG. 10 is a differential scanning calorimetry curve of granules of this invention produced in Example 16 with a drier inlet temperature set at 70° C., and sampled 10 minutes after the sample of FIG. 10 were taken.

FIG. 11 is a differential scanning calorimetry curve of granules of this invention produced in Example 16 with a dryer inlet temperature set at 70° C., and sampled 30 minutes after the sample of FIG. 10 was taken.

FIG. 12 is a differential scanning calorimetry curve of granules of this invention produced in Example 17 with a dryer inlet temperature set at 70° C., and sampled when the granules reached a temperature of 60° C.

FIG. 13 is a differential scanning calorimetry curve of granules of this invention produced in Example 17 by reducing the dryer inlet air temperature from 70 to 60° C., and sampled when the granules were at a temperature of 60° C. for 20 minutes.

FIG. 14 is a differential scanning calorimetry curve of granules of this invention produced in Example 17 by reducing the dryer inlet air temperature from 70 to 60° C., and sampled when the granules were at a temperature of 60° C. for 60 minutes.

FIG. 15 is a differential scanning calorimetry curve of the granules of this invention produced in Example 18.

FIG. 16 is a differential scanning calorimetry curve of the granules of this invention produced in Example 19.

FIG. 17 is a differential scanning calorimetry curve of the granules of this invention produced in Example 20.

FURTHER DETAILED DESCRIPTION OF THIS INVENTION Principal Components

As noted above, there are three principal components in the granules of this invention and in the solid dosage forms of this invention such as tablets, caplets, and hard shell capsules. These are sodium ibuprofen dihydrate, sodium carbonate and polyvinylpyrrolidone. Each of these components is well-known in the art and methods for the preparation of these respective materials are also well-known and are reported in the literature. All such components should be of NF, USP, or multicompendial grade. In other words, they should be of pharmaceutically acceptable purity, grade, and/or quality.

Preparation of Granules of this Invention

To prepare the granules of this invention, the above three principal components are mixed in appropriate proportions relative to each other while wet with water in a high shear granulator. In practice, it is desirable to form a solution of the polyvinylpyrrolidone in water prior to forming the overall mixture of the three components. This will provide a more uniform distribution of polyvinylpyrrolidone in the granules. After blending and granulation in the high sheer granulator, water is removed from the wet granules by a conventional drying procedure such as pan drying in an oven or by fluidized bed drying. Typically, the drying is effected at a temperature of up to about 100° C. Preferably, oven temperatures for drying of the granules is in the range of about 60 to about 70° C. In the case of a fluidized bed dryer, the inlet temperature is also preferably in the range of about 60 to about 70° C. In a particularly preferred drying operation, the temperature of the outlet air is monitored so that the drying is terminated when the outlet air temperature reaches about 40° C. In this way the total moisture content of the granules is in the preferred range of about 12 to about 15, and more preferably is around 13.5 wt %, which is about the amount of hydrate water in sodium ibuprofen dihydrate. The dried product is then sieved to remove oversized material (e.g., greater than 16 mesh). Such oversized material is typically milled and recycled to the granulation operation.

In greater detail, it is preferred to charge the sodium ibuprofen dihydrate into the high shear granulator followed by a preformed solution of polyvinylpyrrolidone in water. After thorough blending of these components the requisite amount of sodium carbonate is then added and the mixture is subjected to additional high shear granulation. The granulation is conducted at a temperature in the range of about 15 to about 35° C., using cooling if necessary to remove excess heat generated during granulation. The rate of shear of the chopper in the high shear granulator prior to addition of the sodium carbonate is typically in the range of about 1000 to about 2000 rpm for a period in the range of about 3 to about 6 minutes. The chopper rate is then reduced to a low shear rate of about 200 to about 500 rpm for an additional period of about 3 to about 6 minutes. After the addition of the sodium carbonate, this same two stage operation of the chopper is repeated (i.e., ca. 1000 to ca. 2000 rpm for ca. 3 to ca. 6 minutes and then ca. 200 to ca. 500 rpm for ca. 3 to ca. 6 minutes).

Depending upon the design of the high shear granulator, the apparatus may contain another mechanism for effecting motion of the mixture in the granulator, which mechanism is known as a paddle. The rate at which the paddle is operated is of lesser importance and thus can be varied. When using a 160 liter, Fluid Air Pharmx High Shear Granulator, Model PX150, it was found convenient to operate the paddle in a two stage manner in which during the first stage the paddle was operated at 100 rpm and in the second stage at 30 rpm. These stages coincided with the two stage operation of the chopper.

The sodium carbonate used in forming the granules should be of NF or USP grade and initially may be hydrated, but preferably is in the form of an anhydrous powder. Polyvinylpyrrolidone of pharmaceutically acceptable grade is available in various forms which may be used in the practice of this invention. However, it is preferred to utilize polyvinylpyrrolidone with a K value in the range of 30 to 120, with a K value of 90 being more preferred. The sodium ibuprofen dihydrate is a racemic mixture of pharmaceutically acceptable grade and preferably is used in powder form.

The amount of sodium carbonate used in forming the granules is typically in the range of about 1 to 4% by weight of the total mixture. Preferably the amount is in the range of about 2 to about 3% by weight of the total mixture. In forming the granules, the amount of polyvinylpyrrolidone is typically in the range of about 1 to about 10% by weight of the total mixture. Preferably, the amount of polyvinylpyrrolidone is in the range of about 2 to about 4% by weight of the total mixture. Preferably, the balance to 100% by weight of the total mixture is composed of sodium ibuprofen dihydrate. If desired, other conventional pharmaceutically-acceptable excipients can be used, provided they do not adversely interact with any of the three principal components or otherwise interfere with the preparation of the granules or solid dosage forms produced therefrom. However, inclusion of such excipients in the granules is not advisable since such usage would reduce the concentration of the sodium ibuprofen dihydrate in the granules and result in increased production costs and record keeping.

The water used is also of sufficient purity to meet regulatory requirements. The amount of water used in forming the granules is typically in the range of about 5 to about 15 wt % of the total weight of the wet mixture of components. Preferably, the amount of water used for granule formation is in the range of about 8 to 12 wt % of the total weight of the wet mixture of components. If too little water is used, insufficient granulation will occur. On the other hand, if too much water is used, the mixture will have the consistency of a bakery dough. In either case, after drying, the product will not have a desirable average (mean) particle size. In this connection, the average particle size of the dry granules is typically in the range of about 150 to about 600 microns, and preferably is in the range of about 200 to about 300 microns.

Especially preferred granules of this invention in wet form are prepared from the following components in the amounts specified: sodium ibuprofen dihydrate, 85.95 wt %; non-crosslinked polyvinylpyrrolidone (especially K-90), 2.25 wt %; anhydrous sodium carbonate powder, 1.80 wt %; purified water, 10 wt %. Especially preferred granules of this invention in dry form have the following composition: 95.50 wt % as sodium ibuprofen dihydrate; 2.50 wt % of polyvinylpyrrolidone (especially K-90); and 2.00 wt % as anhydrous sodium carbonate.

Preferred Granules and Granule Formulations

As indicated above, this invention provides in preferred embodiments granules and granules formulations which are characterized by exhibiting during differential scanning calorimetry a phase transition peaking in the range of about 100° C. to about 102° C., and wherein the size of the DSC peak, which peak corresponds to solids-to-solids phase transition, is at least about 150 joules per gram. The existence of this peaking ensures that the granules, when suitably formulated—as in the formulation designated E) above—will produce solid dosage forms having excellent processing characteristics in a rotary press and that will thereby produce solid dosage forms of high quality and that comply with present day regulatory requirements. There are various ways of ensuring that the granules and the resulting formulation will have the foregoing DSC thermal characteristics during differential scanning calorimetry (DSC). For example, if the granule samples do not exhibit such DSC thermal characteristics:

-   -   The granules can be heated at a temperature and for a period of         time sufficient to achieve the foregoing DSC thermal         characteristics. Suggested heating conditions include heating at         about 30 to about 70° C. for a period of about 5 to about 50         minutes;     -   The time period during which wet granulation is conducted can be         increased. In bench scale operations, this total period of wet         granulation was found to be at least about 12 to 16 minutes.         When the operation is conducted on a larger scale, the total         period of wet granulation may differ at least somewhat from 12         to 16 minutes in order to achieve the desired DSC thermal         characteristics, and thus a few pilot experiments should be         conducted if necessary, in order to determine the appropriate         time period for wet granulation when operating on a larger         scale;     -   Avoid inclusion of components in the granulation processes when         the granules are still wet will cause failure to achieve the         foregoing DSC thermal characteristics. Components found         detrimental in this respect are starch, sodium starch glycolate,         and magnesium stearate. As will be seen from Examples presented         hereinafter, once the granules have been dried, microcrystalline         cellulose can be utilized as a component in formulations for use         in producing solid dosage forms. Indeed, microcrystalline         cellulose is a preferred component for use in such formulations.

The following Examples are presented for the purposes of illustration. They are not intended to limit the invention to only the details and materials set forth therein.

Example 1 Preparation of Granules

Granules composed of 95.5 wt % of sodium ibuprofen hydrate, 2 wt % of sodium carbonate and 2.5 wt % of polyvinylpyrrolidone (Plasdone K-90, International Specialty Products Inc., Wayne, N.J.) were prepared by a wet granulation process of this invention. The process used involved dissolving the Plasdone K-90 in water, adding the solution to sodium ibuprofen dihydrate in a V-blender equipped with a high shear intensifier drive (MAXI-BLEND LAB V-BLENDER manufactured by GlobePharma, Inc., New Brunswick, N.J.), and forming the granule by operating the blender using high shear, adding sieved sodium carbonate powder to the wet mixture in the blender, mixing for another 5 minutes utilizing the intensifier drive. After discharging the blender content into a pan, the granules were dried in an oven maintained at 50° C. until all added water was removed. The product was then sieved through a stainless steel 16-mesh U.S.A. standard sieve.

Example 2 Preparation of Tablets Example 2A

The granules formed as in Example 1 were used to prepare a fully formulated blend for tablet preparation using rotary press. In this operation, the granules were mixed with microcrystalline cellulose (MCC) and colloidal silica by means of dry blending. The formulation processed well in a 10-station rotary press and the resulting tablets showed good friability, dissolution, and disintegration. The final blend was composed of 75 wt % of sodium ibuprofen hydrate, 2.37 wt % of polyvinylpyrrolidone, 1.58 wt % of sodium carbonate, 20.95 wt % of microcrystalline cellulose, and 0.1 wt % of colloidal silica.

The characteristics of the high active-content granules formed as in Example 1 and the tablet formulation formed as in Example 2A are given in Table 1. The flowability index showed that both the granules and the fully formulated blends have good flow characteristics. In addition, the tablets met all desired performance criteria.

TABLE 1 Granules Tablet Formulation Flowability No. 78.5   81.5   Areated Bulk Density 0.641 0.569 Packed Bulk Density 0.687 0.619 Compressibility   6.60%   8.00% Angle of Repose 40.7°   37.0°   Angle of Spatula 45°    44°    Uniformity 6.3  4.4 

Example 2B

Granules formed as in Example 1 were used to prepare a fully formulated blend for tablet preparation using rotary press, as described in Example 2A, except that the granules were mixed with crospovidone by means of dry blending. The formulation processed well in a 10-station rotary press and the resulting tablets showed acceptable friability and good dissolution properties. The final blend was composed of 93.6 wt % of sodium ibuprofen hydrate, 2.45 wt % of polyvinylpyrrolidone, 1.96 wt % of sodium carbonate, and 2 wt % of crospovidone.

Example 2C

Granules formed as in Example 1 were used to prepare a fully formulated blend for tablet preparation using rotary press, as described in Example 2A, except that the granules were mixed with Na croscarmellose by means of dry blending. The formulation flowed well into a 10-station rotary press and the resulting tablets showed acceptable friability and good dissolution properties The final blend was composed of 93.6 wt % of sodium ibuprofen hydrate, 2.45 wt % of polyvinylpyrrolidone, 1.96 wt % of sodium carbonate, and 2 wt % of Na croscarmellose.

Examples 3-10

In these Examples, runs were made using the wet granulation technique in a bench scale high shear granulator, Model PX1, 2-Liter Fluid Air High Shear Granulator. This apparatus includes an impeller and a chopper disposed in a bowl. The impeller rotates in a circular path within the bowl, the blend to be granulated within the bowl and the chopper breaks up large particles formed in the blend during processing. The granulator is operated by compressed air and, in operation, some compressed air enters the bowl and contributes to the formation of a blend having a consistency resembling marshmallow consistency, i.e., the blend is soft and of low density. Upon further blending, part of the trapped air is released. The blend has a wet appearance. The appearance of the resultant granules is significantly different from the granules processed in a twin-shell blender using the same formulation. The granules from a twin-shell blender appear much dryer than the granules produced in the present apparatus.

In a typical operation, after adding sodium ibuprofen dihydrate to the bowl, a lid is placed on the bowl, the chopper and impeller rates are set at 2500 and 300 RPM, respectively. Immediately after turning on the mixing, an aqueous solution of povidone K-90 is poured into the granulator through a hole in the lid. It typically takes about 100 seconds to transfer the liquid to the bowl through the small hole in the bowl cover. After povidone solution transfer, the high shear blending is continued for a preset time. Then the mixing rates of both chopper and impeller are reduced to about half of the original settings and this low shear mixing is continued for another few minutes. Anhydrous sodium carbonate powder (previously sieved through a 20-mesh screen) is then added to the bowl and the mixing continued for another high shear-low shear mixing cycle. The wet granules produced in run 1 were discharged into a beaker before adding to a fluid bed dryer. Dried materials collected in plastic bags show the presence of significant amount of granules of greater than 16 mesh.

The operations involved two stages. In the first stage, sodium ibuprofen dihydrate and polyvinylpyrrolidone (K-90 solution) were added to the granulator and mixed. In the second stage, finely divided anhydrous sodium carbonate was added to the granulator contents from the first stage, and the resultant mixture was processed into granules.

The conditions of wet granulation operation in the first stage of Examples 3-10 are summarized in Table 2. Table 3 summarizes the conditions of wet granulation operation used in the second stage. In Tables 2 and 3, the designation “CPR” designates “chopper”, “IMP” designates “impeller”, and “n/a” designates “not applicable”.

TABLE 2 CONDITIONS USED IN STAGE 1 OPERATION PVP K-90 solution De-lumping addition/mixing Mixing Ex. No. CPR IMP Time CPR IMP Time CPR IMP Time 3 2500 300 15 2500 300 95 2500 300 120 4 2500 300 180 2500 300 300 500 150 300 5 n/a n/a 0 2500 300 90 1000 150 210 6 n/a n/a 0 2500 300 110 1000 150 210 7 n/a n/a 0 2500 300 205 1000 150 210 8 n/a n/a 0 2500 300 180 1000 150 210 9 n/a n/a 0 2500 300 225 1000 150 210 10 n/a n/a 0 2500 300 93 1000 150 210 Units used for chopper & impeller are RPM and time is in seconds, unless otherwise specified.

TABLE 3 CONDITIONS USED IN STAGE 2 OPERATION Ex No. CPR IMP Mixing time CPR IMP Mixing Time 3 2500 300 60 1000 150 0 4 0 0 480 1000 150 360 5 2500 300 90 1000 150 210 6 2500 300 90 1000 150 210 7 2500 300 90 1000 150 210 8 2500 300 90 1000 150 210 9 2500 300 90 1000 150 210 10 2500 300 90 1000 150 210 Units used for chopper & impeller are RPM and for time are seconds, unless otherwise specified.

In Example 4 de-lumping efficiency of the high shear chopper was measured by checking the presence of lumps in the granulator at various blending intervals. It was concluded that de-lumping of sodium ibuprofen dihydrate in its original particulate form is not efficient and de-lumping becomes significantly more efficient after the povidone solution is added. We found no detectable lumps after about 120 seconds at the high shear mixing cycle. After the granulator operation, the contents of the granulator bowl were transferred to a fluidized bed dryer pneumatically using a vacuum tube applied to the hole in the cover and with suction generated by the fluid bed dryer. The dried materials collected showed very little content of granules greater than 16-mesh in size. Because of these findings in Examples 5-10 the de-lumping steps were omitted and vacuum transfer to the fluidized bed dryer was employed.

Example 5 went smoothly and the granules produced looked good. It was decided then that we should check the robustness of the process. There are two aspects of process robustness. The first is the ability of the process to produce granules with the same quality on a consistent basis. The second aspect of process robustness is whether the process can be carried out, independently, with a skilled technician. Accordingly, a skilled technician carried out the operations of Examples 6-10.

In Example 6, in addition to the conditions summarized in Tables 1 and 2, the dryer parameters were documented. The data relating to the dryer operation are summarized in Table 4. In all cases, vacuum transfer to the fluidized bed dryer was used.

TABLE 4 SUMMARY OF DRYER OPERATION IN EXAMPLE 6 Time, Air flow Inlet Outlet Product minutes rate, SCFM temp, ° C. temp, ° C. temp, ° C. 0 8 — — 14 1 9 24  37.8 14 8 8 58.3 39.7 20 12 8 74.2 45.7 32.8 15 8 68.9 40.7 40.7

Evaluations were made of the properties of the granules produced in Examples 4-10. In conducting these evaluations, all the granules from each run were individually sieved and the amounts of material retained on a 16-mesh screen were recorded. The sieved materials were then measured for particle size distribution using the light scattering method. Moisture contents of the granules was determined in two separate laboratories, independent of each other, using moisture balances at a set temperature of 110° C. The results of these evaluations are summarized in Table 5 in which “STDEV” denotes standard deviation and “RSTD” denotes relative standard deviation.

TABLE 5 EVALUATION OF GRANULES Moisture, wt %, weight >16-mesh, loss at 110° C. Size Fraction, Mean Particle By By Ex. No. wt % Size, microns Laboratory 1 Laboratory 2 4 1.9 207 13.4 13.4 5 3.7 252 13.3 13.5 6 2.9 228 13.3 13.3 7 4.5 245 13.2 13.5 8 2.8 263 13.3 13.4 9 2.4 234 13.4 13.3 10  0.6 220 13.4 13.5 Average 2.7 235 13.3 13.4 STDEV 1.3 19 0.1 0.1 % RSTD 47.31% 8.22% 0.60% 0.61%

Distribution of active contents in fractions of the granules was also evaluated. This evaluation involved separately sieving about 100 grams of granules from runs 2 and 8 through a stack of stainless steel sieves. Size fractions in (a) units of wt % and (b) active contents of fractions as determined by HPLC, reported as percentages of theoretical value, are given in Table 6, in which “μ” denotes micron. It can be seen from the results in Table 6 that there is a tendency for the higher active contents to be found in the smaller sized particles.

TABLE 6 WEIGHT AND ACTIVE CONTENTS OF SIEVED FRACTIONS OF DIFFERENT SIZES Run #8 Run #2 Theoretical Theoretical Sieve Active Sieve Active Sieves Opening Retention content Retention Content 16 mesh (1180μ) 0.60% 98.0% 1.9% 98.8% 30 mesh (600μ) 0.33% 79.2% 40 mesh (425μ) 0.48% 55.3% 60 mesh (250μ) 15.53% 94.2% 17.0% 96.8% 80 mesh (180μ) 29.22% 98.4% 33.9% 99.8% 100 mesh (150μ) 23.97% 99.3% 26.5% 102.1% 200 mesh (75μ) 22.64% 102.9% 19.0% 103.1% pan (<75μ) 7.25% 100.9% 2.5% 103.7%

The evaluation of the granules indicates that from the standpoints of particle size distribution, active content in varying size fractions, and particle friability point of view, the process is quite robust.

Experiments were conducted in order to evaluate the performance of granules produced in some of the above Examples in tablet formation. Granules from Examples 9 and 10 in their original sealed bags were placed in a 50° C. oven for 20 hours and, after allowing them to cool to room temperature, these granules were combined together to form a larger blend. The combined granules were then blended with excipients to produce a formulation containing 75 wt % sodium ibuprofen dihydrate. This formulation was then converted into tablet form on a rotary press. It was observed that no punch coating occurred when the blend was pressed into tablets on the rotary press. It was also observed that no punch coating occurred when granules from Example 5 were formulated and pressed into tablets on the rotary press.

The composition of the formulation used in producing the tablets (sometimes hereinafter designated Formulation DTH) is 75% of sodium ibuprofen dihydrate, 21.37% of microcrystalline cellulose (MCC PH102; FMC Corporation), 1.96% PVP K-90 (Plasdone K-90, International Specialty Products Inc., Wayne, N.J.), 1.57% anhydrous sodium carbonate, and 0.10% colloidal silica (Aerosil 200; Evonik Industries, formerly Degussa Corporation). The tablet formulation is prepared by blending the granules with the microcrystalline cellulose and colloidal silica. For every 100 parts by weight of granules used for the DTH preparation, 21.21 parts by weight of microcrystalline cellulose and 0.127 parts by weight of colloidal silica are incorporated.

To prepare Formulation DTH, the following procedure is recommended: de-lump the granules and microcrystalline cellulose by sieving them separately through a 16-mesh screen. Weigh all three ingredients separately, prepare a preblend of colloidal silica and microcrystalline cellulose by mixing the colloidal silica and a portion of microcrystalline cellulose, pass this mixture through a 20-mesh sieve. Discharge the granules, the remaining microcrystalline cellulose, and the preblend into a low shear blender and blend for 10 minutes.

It is to be understood that Formulation DTH, while constituting a preferred formulation of this invention, should not be construed as limiting this invention to this particular formulation. For example, good results can be achieved by eliminating the sodium croscarmellose component from Formulation DTH. Other formulations utilizing the granules of this invention based on this disclosure may now occur to those of ordinary skill in the art.

Differential scanning calorimetry (DSC) scans of most of the granule samples produced in Examples 3-10 indicated the occurrence of an exothermal reaction just before a major solid state transition peaking around 100° C. The exothermal transition disappeared after holding the granules at elevated temperature (50° C.) conditions for a short time period. The position of the transition and the disappearance of the anomaly after holding granules under elevated temperature conditions indicated that the exothermal peak was related to stress in the granules.

Examples 11-20 involve experimental work conducted in order to determine what causes the stress and how to eliminate the stress, which appeared to be related to drying conditions. In addition to studying drying conditions, blending time in the wet granulation process was generally increased from 10 to 16 minutes. The experiments were conducted at batch sizes of 0.5 kg.

Examples 11-20

The procedures used in Examples 11-20 involved wet granulation of the components, drying of the granules, and analysis of the granules. In the granulation, operations of all Examples except Example 20, samples from the same specific lot of sodium ibuprofen dihydrate were used. In Example 20, the sodium ibuprofen dihydrate was a composite mixture of products from small bench scale crystallizations of sodium ibuprofen dihydrate recovered from an ibuprofen product sodium stream. This latter bench scale sodium ibuprofen dihydrate had a particle size several times greater than that of the lot of sodium ibuprofen dihydrate used in Examples 11-19. The granulation processing steps used involved (i) discharging sodium ibuprofen dihydrate (Na IBU) into the granulator bowl of the high shear granulator, (ii) de-lumping Na IBU, (iii) adding povidone solution to promote granulation under high shear, (iv) adding anhydrous sodium carbonate powder into the blend and resume blending, and (v) transferring granules to a fluidized bed dryer for drying. Only in Example 12 was a de-lumping step used. In Example 12, before addition of PVP solution, sodium ibuprofen dihydrate was de-lumped for 90 seconds by operating the chopper at 2500 RPM and at an impeller speed of 300 RPM. At the end of de-lumping, PVP solution was poured into the granulator and the chopper and impeller speed were maintained at the same rates for set periods of time. Then, the speeds were reduced to enable granulation at reduced shear. Afterwards, the granulator was stopped and the lid was removed. Sodium carbonate (<20 mesh) was then sprinkled on the blend. The lid was placed back and blended for about 5 minutes at 2500 RPM chopper and 300 RPM impeller speed and another 5 minutes at 1000 RPM chopper and 150 RPM impeller speeds. Table 8 summarizes the operation parameters for the high-shear granulation, for the de-lumping operation, and for the addition of the polyvinylpyrrolidone (PVP) solution. In Table 8, “CPR” again designates “chopper” and “IMP” designates “impeller”.

TABLE 8 WET GRANULATION PROCESS - DE-LUMPING DURING & AFTER ADDITION OF PVP SOLUTION PVP solution during addition De-lumping and after addition CPR IMP Time CPR IMP Time CPR IMP Time Ex. No. RPM RPM sec RPM RPM sec RPM RPM sec 11 — — — 2500 300 90 1000 150 210 12 2500 300 90 2500 300 200 1000 150 300 13 — — — 2500 300 200 1000 150 300 14 — — — 2500 300 300 1000 150 300 15 — — — 2500 300 300 1000 150 300 16 — — — 2500 300 300 1000 150 300 17 — — — 2500 300 300 1000 150 300 18 — — — 2500 300 300 1000 150 300 19 — — — 2500 300 300 1000 150 300 20 — — — 2500 300 300 1000 150 300

Table 9 summarizes the operating conditions used in the wet granulation process after adding the powdery anhydrous sodium carbonate to the contents in the granulator. In this way, the wet granulation procedure was completed. In Table 9, “CPR” again designates “chopper” and “IMP” designates “impeller”. The term “n/a” designates “not applicable”.

TABLE 9 OPERATION CONDITIONS AFTER SODIUM CARBONATE ADDITION After sodium carbonate addition Holding Time CPR IMP CPR IMP Time before Drying, Trial RPM RPM Time sec RPM RPM sec minutes 11 2500 300 90 1000 150 210 n/a 12 2500 300 300 1000 150 300 n/a 13 2500 300 300 1000 150 300 n/a 14 2500 300 120 1000 150 240 30 15 2500 300 120 1000 150 240 n/a 16 2500 300 120 1000 150 240 n/a 17 2500 300 120 1000 150 240 n/a 18 2500 300 120 1000 150 240 n/a 19 2500 300 120 1000 150 240 n/a 20 2500 300 90 1000 150 210 n/a

At the end of the granulator operations, all of the wet granules were pneumatically transferred immediately to a fluidized bed dryer except for Example 14. In Example 14, the wet granules were kept in the granulator for 30 minutes before they were pneumatically transferred to the fluidized bed dryer for drying. The use of such holding time was for the purpose of determining whether stress in the wet granules may be released by allowing them to stand for a period of time prior to drying.

Table 10 outlines drying parameters used in this study. The base case for drying was use of an inlet air temperature of 70° C. with a product temperature of 40° C. as a control for moisture content as determined by weight loss at 110° C. Examples 11, 12, 13, 14, and 20 were conducted with inlet temperature set at 70° C., and the drying operations were terminated once product temperature reached 40° C. Example 15 was performed with inlet temperature set at 70° C., however samplings were carried out when product temperature reached 35, 40, 45 and 48° C. Instead of using product temperature as a control, Examples 16 and 17 used drying time as the control. In Example 16, at an inlet temperature of 70° C., the first sample for analysis was collected when product temperature reached 40° C., and the drying was continued at the same inlet temperature with additional samples being collected after additional 10 and 30 minutes of drying, respectively. In Example 17, at an inlet temperature of 70° C., the first sample was collected when product temperature reached 40° C. At this point, the inlet temperature was reduced to 60° C. and additional samples were collected after additional drying periods of 20 and 60 minutes, respectively. Example 18 employed an inlet temperature of 80° C. and Example 19 used an inlet temperature of 60° C. Table 10 provides a summary of these operations.

TABLE 10 FLUID BED DRYING CONDITIONS AND SAMPLING POINTS Sampling Point Ex. Inlet Sampling Point Based Based on Drying No. temp on Product Temperature Time, Minutes 11 70° C. 40° C. — — — — — — 12 70° C. 40° C. — — — — — — 13 70° C. 40° C. — — — — — — 14 70° C. 40° C. — — — — — — 15 70° C. 35° C. 40° C. 45° C. 48° C. — — — 16 70° C. 40° C. — — — 70° C. 10 30 17 70° C. 40° C. — — — 60° C. 20 60 18 80° C. 40° C. — — — — — — 19 60° C. 40° C. — — — — — —

The samples from these operations were then subjected to the following analyses:

DSC Phase Transition and Moisture Content

Table 11 provides differential scanning calorimeter data and moisture content, as determined by moisture balance of granules collected under varying fluid bed drying conditions. The data show that about all granules with a moisture content of 13.0% or greater have a heat of transition >170 joule/gram. It is also clear that over drying may lead to lower heat of phase transition. Nevertheless, overdried samples that provide DSC thermal treatment curves which peak in the range of about 100° C. to about 102° C., and which the size of the DSC peak, which peak corresponds to solids-to-solids phase transition, is at least about 150 joules per gram, will give satisfactory results when utilized in forming solid dosage forms.

TABLE 11 DIFFERENTIAL SCANNING CALORIMETRY AND MOISTURE WEIGHT LOSS OF GRANULES AT 110° C. Example Number & Location of Weight Loss Further Sample Phase Transition Heat of at 110° Identification where initial, peak, Transition C., wt. % Applicable ° C. ° C. Joule/g Wt. % 11 98.9 100.7 173.1 13.16 12 98.5 100.6 173.1 13.30 13 98.6 100.7 173.3 13.37 14 98.7 100.5 175.1 13.36 15-35° C. 98.7 100.7 172.9 13.49 15-40° C. 98.6 100.5 174.9 13.45 15-45° C. 98.7 100.6 168.9 11.96 15-48° C. 98.0 101.4 147.7 9.31* 16-70° C. - 0 min 98.8 100.7 177.0 13.03 16-70° C. - 10 min 98.8 100.9 166.2 11.48 16-70° C. - 30 min 97.7 101.7 144.1 7.33* 17-60° C. - 0 min 98.7 100.8 178.0 13.11 17-60° C. - 20 min 98.1 101.7 159.3 11.01 17-60° C. - 60 min 97.8 101.1 130.0 5.46* 18 98.7 100.6 172.9 12.99 19 98.8 100.6 167.6 12.12 20 98.4 100.9 173.3 13.06 *This sample is deemed overdried and thus is not a preferred sample; however, it exhibited desirable DSC thermal characteristics and thus may be used in preparing solid dosage forms.

Particle Size Distributions

Particle size distributions of granules show that all granules have narrow size distributions with the exception of Example 20, which as prepared from a composite sodium ibuprofen dihydrate crystallized from ibuprofen product sodium stream (PSS). The average mean particle size for granules generated from the sodium ibuprofen dihydrate lot used in Examples 11-19 was 172 microns with a standard deviation of 12 microns. The mean particle size of the composite sodium ibuprofen dihydrate used in Example 20 was 324 microns and the granule prepared had a mean particle size of 232 microns.

The similarity of the mean particle size and size distribution of the granules from Examples 11 through 19 indicates that the process is very robust, as regards particle size distribution. The differences of mean size and size distribution as between Examples 11-19 and Example 20 suggests that particle size of granules is a function of the particle size of the starting sodium ibuprofen dihydrate.

Sieve Analyses and Assay Content in Varying Sieve Size Fractions

Twenty grams of granules from Example 12 and 18 were placed on a stack of 12-inch diameter sieves consisting 20, 30, 40, 60, 80, 100, and 200 mesh stainless steel sieves. After shaking for 20 minutes, granules retained on each sieve were weighed and the retained granules of selected size fractions were submitted for HPLC assay determination. The assay contents expressed as wt % of theoretical are given in Table 12 below. The data show that about 90 wt % of the particles are in the 40-200 mesh range and generally lager particle size corresponds to higher assay content. It also shows that the difference in assay content for majority of the particles (40-200 mesh range) is negligible.

TABLE 12 GRANULE SIEVE RETENTIONS AND ASSAY CONTENTS Sieve Retention, wt % Assay, wt % of Theoretical Source of Example Example Example Example Granule 12 18 12 18 20 mesh 2.0 2.0 79 77 30 mesh 0.5 0.5 40 mesh 0.5 0.5 60 mesh 11.8 17.2 93 97 80 mesh 25.0 28.9 97 98 200 mesh  52.0 43.6 Pan (<200 mesh) 8.3 7.4 102 102

In order to demonstrate the advantages of utilizing granules produced pursuant to this invention, granules produced in Example 11, 12, 13, 18, 19, and 20 were blended individually with other excipients to produce a formulation, in this case Formulation DTH, for use in forming tablets. The individual Formulation DTH blends were then sequentially fed into a 10-station rotary press (Minipress II; GlobePharma, Inc., New Brunswick, N.J.) to prepare tablets containing about 600 mg of ibuprofen equivalent of the sodium salt. The main compression was kept at about 10 kilonewton (KN), pre-compression was kept at about 1.5 KN and the production rate was kept in the range of 100-120 tablets per minute. Tablet samples were collected throughout the runs. At least one set of tablet sample of about 30 tablets was collected for each blend. A total of 12 tablet sample sets were collected from the seven Formulation DTH blends processed through the tablet preparation process.

Dissolution of the tablets shows an average theoretical dissolution of 59% at 10 minutes, 98% dissolution at 20 minutes and 13.9 minutes at 80% dissolution. The dissolution rates of Formulation DTH tablets tested were significantly better than regulatory dissolution rates.

Average friability for 100 drops was 0.14 wt % for all 12 sets of tablets collected.

Referring now to the drawings, FIGS. 1-17 are differential scanning calorimetry curves of granules of this invention produced in Examples 11 through 20 and as discussed in relation to Table 11 and summarized under the Brief Description of the Drawings. As noted in connection with that Table, the samples of FIGS. 8, 11, and 14 were deemed usable but are not preferred because of having been overdried during the drying step.

The composition of one type of preferred granules of this invention and the composition of one type of preferred formulation for producing tablets of this invention are described in Table 13. Batch sizes and compositions of such preferred granules and of a preferred tablet formulation of this invention are described in Table 14.

TABLE 13 FORMULATIONS OF GRANULES AND DTH BLEND Wet Dry Granules Granules Formulation DTH Na ibu dihydrate 85.95% 95.50%  75.00% G2.5P2A — — 78.53% PVP K90  2.25% 2.50% 1.96% Na2CO3  1.80% 2.00% 1.57% MCC PH 102 — — 16.37% 16.37% Na Croscarmellose — — 5.00% 5.00% Colloidal Silica — — 0.10% 0.10% Purified Water 10.00% Total 100.00%  100.00%  100.00% 100.00%

TABLE 14 BATCH SIZES AND COMPOSITIONS OF GRANULES AND DTH BLEND Formulation of Formulation of Granules DTH Blend Batch size, dry, kg 40.00  50.93  Sodium Ibuprofen Dihydrate, kg 38.20  — Granules, kg — 40.00  Polyvinylpyrrolidone K-90, kg 1.00 — Anhydrous Sodium Carbonate, kg 0.80 — Mirocrystalline cellulose, kg — 8.34 Sodium Croscarmellose, kg — 2.55 Colloidal Silica, kg — 0.05 Purified Water, kg 4.44 —

A typical procedure for the preparation of one type of preferred granules of this invention at 40 kg dry batch size scale is as follows:

1. Initial Preparations

-   -   a. Prepare a PVP stock solution (18.37 wt %) enough for several         runs by dissolving polyvinylpyrrolidone (PVP K-90) in water         using a high shear blender (3 kg in 13.33 kg purified water).     -   b. Sieve sodium carbonate through a 20 mesh screen either by         hand or using a mill equipped with a 20 mesh screen.

2. Granulation

-   -   a. Weigh and charge 38.20 kg of sodium ibuprofen dihydrate into         a high shear granulator.     -   b. Weigh and charge 5.44 kg of the PVP solution to the         granulator which is operating under high shear. After 4 minutes,         switch to low shear operation and continue operation for another         4 minutes.     -   c. Weigh sieved anhydrous sodium carbonate (0.80 kg) and add to         the granulator under high shear for 4 minutes followed by         another 4 minutes under low shear.     -   d. Pneumatically transport granules to a fluid bed dryer, keep         granules gently fluidized, and start drying with inlet         temperature set at 60° C.

3. Drying Procedure

-   -   a. Set inlet temperature at 60° C., monitor bowl and outlet         temperatures, sample dryer periodically and stop drying when         product temperature reaches about 40° C.     -   b. Determine moisture content (Karl Fischer or moisture balance         at 110° C.) from samples collected with moisture content of 13.4         wt % as the target.

4. Particle Size Adjustment

-   -   a. Pass the dry granules through a 16-mesh sieve to remove >16         mesh particles. Record the weight of >16 mesh material.     -   b. Mill >16 mesh granule through a size reducer and add to the         <16 mesh portion.     -   c. Retain a few hundred grams for quality control and weigh the         remaining <16 mesh product.     -   d. If not used for preparing tablets, store the granules in         fiber drums with polyethylene lining.

5. Analyses

-   -   a. Particle distributions through sieving using 16, 20, 40, 60,         80, 100 and 200 mesh screens.     -   b. Determine moisture content (Karl Fischer or moisture balance         at 110° C.).

One type of preferred formulation of this invention is formed from the preferred granules made as just described above, and has the composition shown in the table below.

Component Amount Na ibuprofen 70 wt % Sodium carbonate 1.47 wt % Plasdone K-90 1.83 wt % MCC 21.60 wt % Crospovidone 2.0 wt % Starch 1500 2.0 wt % Silica 0.1 wt % Stearic Acid 1.00 wt % The above formulation also produced high quality tablets using a 10-station rotary press (Minipress II; GlobePharma, Inc., New Brunswick, N.J.) to prepare tablets containing about 400 mg of ibuprofen equivalent of the sodium salt. Dissolution of the tablets made from this formulation showed an average theoretical dissolution of over 80% at 20 minutes. This is far better than the regulatory requirement of 80% at 60 minutes. For these tablets, the average friability for 100 drops was 0.23 wt %.

A typical procedure for the preparation of one type of preferred tablets of this invention from a preferred tablet formulation of this invention (Formulation 75) is as follows:

-   1. Determine the required quantities of the three excipients     (microcrystalline cellulose, sodium croscarmellose, and colloidal     silica) by multiplying the amount of granules produced as above,     available for blending to the appropriate conversion factor. For     examples, if 40 kg of granules is to be blended for preparation of     Formulation DTH, the microcrystalline cellulose (MCC) requirement is     then 8.34 kg (40 kg×0.2084, the latter number being the conversion     factor for MCC), the sodium croscarmellose requirement is 2.56 kg     (40 kg×0.0637, the latter number being the conversion factor for     sodium croscarmellose), and colloidal silica requirement is 0.051 kg     (40 kg×0.00127, the latter number being the conversion factor for     colloidal silica). -   2. Sieve MCC and croscarmellose sodium separately through a 16-mesh     screen and set aside the respective required weighed quantities of     these two separate excipients. Set aside about 500 grams of the MCC     in a plastic bag (e.g., using a bag of 2-5 liter size). -   3. Weigh and add colloidal silica to the bag containing MCC, mix the     bag contents, break up any lumps by hand, and screen the mixture     through a 20-mesh screen. -   4. Charge the granules, MCC, sodium croscarmellose and pre-blend     into a twin-shell blender, and blend for 10 minutes under low shear. -   5. Discharge the blend into a fiber drum with polyethylene liner and     retain a 500 gram sample. -   6. Analyses     -   a. Particle distributions by sieving using a stack of sieves         consisting of 16, 20, 40, 60, 80, 100 and 200 mesh screens.     -   b. Moisture content (Karl Fischer or moisture balance at 110°         C.).     -   c. Flow characterizations (Flodex and flowability index). -   7. Prepare tablets from Formulation DTH using a rotary press     operated under conventional conditions.

Following our illustrative formulations of this invention suitable for preparation of solid dosage form.

Formulation AA) is a formulation which comprises:

-   -   About 40 to about 100 wt % of a formulation formed from         components which comprise a granule composition formed from         components in powder form, which components comprise (i) 80 to         98 parts by weight of sodium ibuprofen dihydrate on a dry         basis, (ii) 1 to 4 parts by weight of anhydrous sodium carbonate         on a dry basis, and (iii) 1 to 15 parts by weight of         non-crosslinked polyvinylpyrrolidone on a dry basis;     -   0 to about 25 wt % of microcrystalline cellulose, calcium         hydrogen phosphate, or both;     -   0 to about 8 wt % of crospovidone or sodium croscarmellose;     -   0 to about 0.5 wt % of colloidal silica;     -   0 to about 10 wt % starch; and     -   0 to about 2 wt % stearic acid, magnesium stearate, or both.

Formulation BB) is a formulation in which the amount of the granule composition is in the range of about 70 to about 100 wt %, the amount of microcrystalline cellulose is 0 to about 20 wt %, and the amount of crospovidone or sodium croscarmellose is 0 to about 8 wt %, and the amount of colloidal silica is about 0.05 to about 0.2 wt %.

Formulation CC) is a formulation in which the amount of the granule composition is in the range of about 75 to about 100 wt %, the amount of microcrystalline cellulose is 0 to about 20 wt %, and the amount of crospovidone or sodium croscarmellose is 0 to about 6 wt %, and the amount of colloidal silica is 0 to about 0.2 wt %.

Formulation DD) is a formulation in which the amount of the granule composition is in the range of about 60 to about 90 wt %, the amount of microcrystalline cellulose, calcium hydrogen phosphate dihydrate, or both, is about 10 to about 30 wt %, the amount of starch is 0 to about 6 wt %, the amount of crospovidone or sodium croscarmellose is 0 to about 6 wt %, the amount of colloidal silica is 0 to about 0.25 wt %, and the amount of stearic acid, magnesium stearate, or both, is 0 to about 2 wt %.

Formulation EE) is a formulation in which the amount of the granule composition is in the range of about 85 to about 100 wt %, the amount of microcrystalline cellulose, calcium hydrogen phosphate dihydrate, or both, is 0 to about 10 wt %, the amount of starch is 0 to about 6 wt %, the amount of crospovidone or sodium croscarmellose is 0 to about 5 wt %, the amount of colloidal silica is 0 to about 0.25 wt %, and the amount of stearic acid, magnesium stearate, or both, is 0 to about 2 wt %.

This invention also provides solid dosage form formed from a formulation of any of AA), BB), CC), DD), or EE). Also provided by this invention are dosage forms which comprise a hard-shell capsule containing a granule composition formed from components in powder form, which components comprise (i) 80 to 98 parts by weight of sodium ibuprofen dihydrate on a dry basis, (ii) 1 to 4 parts by weight of anhydrous sodium carbonate on a dry basis, and (iii) 1 to 15 parts by weight of non-crosslinked polyvinylpyrrolidone on a dry basis. In addition, this invention provides a method of preparing solid dosage forms of sodium ibuprofen dihydrate, which method comprises compressing in a rotary press a granule composition as described in the immediately preceding sentence.

Components referred to by chemical name or formula anywhere in the specification or claims hereof, whether referred to in the singular or plural, are identified as they exist prior to coming into contact with another substance referred to by chemical name or chemical type (e.g., another component, a solvent, or etc.). It matters not what chemical changes, transformations and/or reactions, if any, take place in the resulting mixture or solution as such changes, transformations, and/or reactions are the natural result of bringing the specified components together under the conditions called for pursuant to this disclosure. Thus the components are identified as ingredients to be brought together in connection with performing a desired operation or in forming a desired composition. Also, even though the claims hereinafter may refer to substances, components and/or ingredients in the present tense (“comprises”, “is”, etc.), the reference is to the substance, component or ingredient as it existed at the time just before it was first contacted, blended or mixed with one or more other substances, components and/or ingredients in accordance with the present disclosure.

Except as may be expressly otherwise indicated, the article “a” or “an” if and as used herein is not intended to limit, and should not be construed as limiting, a claim to a single element to which the article refers. Rather, the article “a” or “an” if and as used herein is intended to cover one or more such elements, unless the text expressly indicates otherwise.

The invention may comprise, consist or consist essentially of the materials and/or procedures recited herein.

This invention is susceptible to considerable variation in its practice. Therefore the foregoing description is not intended to limit, and should not be construed as limiting, the invention to the particular exemplifications presented hereinabove. 

1. A process of preparing highly dispersible free-flowing granules of sodium ibuprofen dihydrate, which method comprises: bringing together in a high shear granulator components comprised of (i) at least 80 parts by weight on a dry basis of sodium ibuprofen dihydrate, (ii) 1 to 4 parts by weight on a dry basis of sodium carbonate, (iii) 1 to 15 parts by weight on a dry basis of non-crosslinked polyvinylpyrrolidone, and (iv) 8 to 12 parts by weight of water based on the total weight of (i), (ii), (iii), and (iv) to form a wet mixture; granulating said wet mixture in said high shear granulator to form wet granules; drying wet granules to form dried granules having a moisture content in the range of about 12.5 to 15 wt % as determinable by measurement of weight loss at 110° C.; and removing by sieving dried granules having a particle size greater than 16 mesh.
 2. A process as in claim 1 wherein the granulation of said wet mixture in said high shear granulator is conducted for a period of time such that after drying said wet mixture, the dried granules exhibit during differential scanning calorimetry a phase transition peaking in the range of about 100° C. to about 102° C., and wherein the size of the DSC peak, which peak corresponds to solids-to-solids phase transition, is at least about 150 joules per gram.
 3. A process as in claim 2 wherein said components (iii) and (iv) are premixed to form a solution, and wherein said solution and (i) and (ii) are brought together in the high shear granulator, and optionally wherein said solution is introduced into said high shear granulator containing component (i) and after mixing the resultant mixture in said granulator, component (ii) is introduced into said granulator and the resultant mixture is then granulated.
 4. A process as in claim 1 wherein the granulation is conducted at a temperature in the range of about 15 to about 35° C., using cooling if necessary to remove excess heat generated during granulation.
 5. A process as in claim 1 wherein said wet granules are dried to a moisture content in the range of about 12 to about 15 wt % as determinable by measurement of weight loss at 110° C.
 6. A process as in claim 1, wherein upon completion of the wet granulation the granules are transferred pneumatically to a fluidized bed dryer and are promptly dried therein.
 7. A process as in claim 1, wherein said drying is conducted in a fluidized bed drier operated with an inlet air temperature in the range of 60 to about 70° C., and wherein the operation of said drier is terminated when the temperature of the outlet air reaches about 40° C.
 8. A process as in claim 1, wherein the granulation is conducted at a temperature in the range of about 15 to about 35° C., using cooling if necessary to remove excess heat generated during granulation; wherein upon completion of the wet granulation the granules are transferred pneumatically to a fluidized bed dryer and are promptly dried therein by operating said dryer with an inlet air temperature in the range of 60 to about 70° C., and wherein the operation of said drier is terminated when the temperature of the outlet air reaches about 40° C.
 9. A highly dispersible, free-flowing granule composition having a high content of sodium ibuprofen dihydrate, which composition is formed from components in powder form, said components comprising (i) 80 to 98 parts by weight of sodium ibuprofen dihydrate on a dry basis, (ii) 1 to 4 parts by weight of anhydrous sodium carbonate on a dry basis, and (iii) 1 to 15 parts by weight of non-crosslinked polyvinylpyrrolidone on a dry basis.
 10. A granule composition as in claim 9, wherein said composition is formed from components comprising (i) about 95 parts by weight of sodium ibuprofen dihydrate on a dry basis, (ii) about 2 to 3 parts by weight of anhydrous sodium carbonate on a dry basis, and (iii) about 2 to 3 parts by weight of non-crosslinked polyvinylpyrrolidone on a dry basis.
 11. A granule composition as in claim 9 wherein said dried granule exhibits during differential scanning calorimetry a phase transition peaking in the range of about 100° C. to about 102° C., and wherein the size of the DSC peak, which peak corresponds to solids-to-solids phase transition, is at least about 150 joules per gram.
 12. A granule composition as in claim 9 wherein said granules have a moisture content in the range of about 11 to about 15 wt %, as determinable by measurement of weight loss at 110° C.
 13. A wet granule composition having a high content of sodium ibuprofen dihydrate, which composition is formed from components in powder form, said components comprising (i) sodium ibuprofen dihydrate in an amount of at least 80 wt % on a dry basis, (ii) anhydrous sodium carbonate in an amount in the range of 1 to 4 wt % on a dry basis, (iii) non-crosslinked polyvinylpyrrolidone in an amount in the range of 1 to 15 wt % on a dry basis, and (iv) water in an amount in the range of 8 to 12 wt % based on the total weight of (i), (ii), (iii), and (iv).
 14. A wet granule composition as in claim 13 wherein said composition is formed from components comprising (i) sodium ibuprofen dihydrate in an amount of about 95 wt % on a dry basis, (ii) anhydrous sodium carbonate in an amount of about 2 to 3 wt % on a dry basis, (iii) non-crosslinked polyvinylpyrrolidone in an amount of about 3 to 2 parts by weight on a dry basis, and (iv) water in an amount in the range of about 8 to 12 wt % based on the total weight of (i), (ii), (iii), and (iv).
 15. A sodium ibuprofen dihydrate formulation adapted for preparation of solid dosage forms using a rotary press, which formulation is formed from components which comprise: about 40 to about 100 wt % of a granule composition as in claim 9; 0 to about 25 wt % of microcrystalline cellulose, calcium hydrogen phosphate, or both; 0 to about 8 wt % of crospovidone or sodium croscarmellose; 0 to about 0.5 wt % of colloidal silica; 0 to about 10 wt % starch; and 0 to about 2 wt % stearic acid, magnesium stearate, or both.
 16. A formulation as in claim 15 wherein the amount of the granule composition is in the range of about 70 to about 100 wt %, the amount of microcrystalline cellulose is 0 to about 20 wt %, and the amount of crospovidone or sodium croscarmellose is 0 to about 8 wt %, and the amount of colloidal silica is 0 to about 0.2 wt %.
 17. A formulation as in claim 15 wherein the amount of the granule composition is in the range of about 90 to about 100 wt %, the amount of microcrystalline cellulose is 0 to about 10 wt %, and the amount of crospovidone or sodium croscarmellose is 0 to about 6 wt %, and the amount of colloidal silica is 0 to about 0.2 wt %.
 18. A formulation as in claim 15 wherein the amount of the granule composition is in the range of about 60 to about 90 wt %, the amount of microcrystalline cellulose, calcium hydrogen phosphate dihydrate, or both, is about 10 to about 30 wt %, the amount of crospovidone or sodium croscarmellose is 0 to about 6 wt %, the amount of starch is 0 to about 6 wt %, the amount of stearic acid, magnesium stearate, or both, is 0 to about 2 wt %, and the amount of colloidal silica is 0 to about 0.25 wt %.
 19. A formulation as in claim 15 wherein the amount of the granule composition is in the range of about 85 to about 100 wt %, the amount of microcrystalline cellulose, calcium hydrogen phosphate dihydrate, or both, is 0 to about 10 wt %, the amount of starch is 0 to about 6%, the amount of crospovidone or sodium croscarmellose is 0 to about 5 wt %, the amount of colloidal silica is 0 to about 0.25 wt %, and the amount of stearic acid, magnesium stearate, or both, is 0 to about 2 wt %.
 20. A solid dosage form formed from a formulation as in claim
 15. 21. A dosage form which comprises a hard-shell capsule containing a granule composition as in claim
 9. 22. A method of preparing solid dosage forms of sodium ibuprofen dihydrate, which method comprises compressing in a rotary press a granule composition as in claim
 9. 